Roller boring-drill.



R. HUGHES.

ER BORING DRILL.

APP IIIIIIIIIIIIII BB. 111111 s. 1,119,163. 1 PatentedDec. 1, 1914.

I 1 1 I a PATENT OFFICE.

HOWARD ROBARID HUGHES, OF HO USTON, TEXAS.

ROLLER BORING DRILL,

To all whom it may concern I Be it known that I, IIOWARD R. HUGHES, acitizen of the United States, residing at Houston, Texas, have inventeda certain new and useful-Improvement in Roller Boring- Drills, of whichthe following isa full, clear, and exact description, such as willenable others skilled in the art to which it appertains to make and usethe same.

This invention relates to boring drills of the ty e in which the cuttingdevices consist of rol ers that are rotatably mounted on the head of thedrill.

The main object of my present invention is to provide a roller boringdrill which is so designed that it will dril a hole of much greaterdiameter than the extreme diameter of the drill head includingthecutting rollers on said head which usually project laterally a slightdistance from the head, thereby making it possible to drill a hole ofgreater diameter than the diameter of a well casing which is just largeenough to permit the drill to be inserted in same.

Another object is to provide a roller drillhaving aneccentrically-disposed cutting roller or a roller which projectslaterally some distance from one side of the head of the drill, saidroller being so proportioned and arranged that it does not interferewith the operation of the main cutting rollers on the drillas itsprincipal function is to maintain siiflicient clearance at all times toinsure a hole large enough for the casing to follow freely, therebyenabling the casing to be forced down into the hole progressively so asto prevent the walls of the hole from caving in. And still anotherobject is to provide a roller drill having. the characteristicsabove-mentioned that can be manufactured cheaply.

Other objects and desirable features of my' invention will behereinafter pointed out.

Figure 1 of the drawings is anelevational view of a roller drillconstructed in accordance with my invention, a .portion of the sleeveand the stem of the drill being in vertical section; Fig. 2 is a detailsectional view showing the way that the eccentrically-dis posed cuttingroller is mounted on the head; and Fig. 3 is a detail sectional viewshowing one of the main cutting rollers provided with an integralportion that constitutes an eccentrically-disposed cutting means.

I have herein shown my invention embodied in a roller boring drill ofthe type de- Specifleafl on of Letters ratent.

Patented Dec. 1-, 1914.

Application filed February 10, 1913. Serial No. 747,495.

scribed in my prior Patent N 0. 979,496, dated December 27, 1910, but Ido not wish it to be understood that the invention is limited to a drillof this type. i

Referring to F' gs. 1 and 2 of the drawings which illustrate thepreferred form of my invention, 1 and 2 designate the two sections ofthe head of the drill which are clamped together by a sleeve 3 thatsecures the head to the tubular-shaped stem 4 of the drill. The drill isprovided with a pair of main cutting rollers A and B which areapproximately frusto-conical-shape, and said rollers are arrangeddiametrically opposite each other on s indles that project downwardlyand inwar ly toward the longitudinal center of the head so that theywill form a hole thatis concentric with the head. Said rollers can besecured on their supporting spindles in various ways as, for example, inthe manner illustrated and described in my prior patent above referredto. A A third roller G, which I will refer to as aneccentrically-disposed cutting roller,-is mounted on the it acts on thematerial that surrounds the hole formed by the main cutting rollers Aand B and thus enlarges or increases the diameter of said hole. Theroller 0 is also approximately frusto-conical-shape and it is mountedbehind one of the main cutting rollers, the roller B, at the base end ofsame. the small end of the roller 0 being of approximately the samediameter as'the base endor large end of the main cutting roller B andhaving substantially the same taper as said roller B so that itpractically forms a continuation of same, as shown in Fig. 1.

By mounting the roller C in this manner I obtain a cutting surface atone side of the head which lies outside of the path of travel of themain cutting surfaces of the drill, thereby producing a drill in whichthe cutting surface at one side ofthe longitudinal. axis of'the head isgreater than the cutting surface at the other side of the longitudinalaxis. The inclined spindle 5 on which the main cutting roller B ismounted projects forwardly from a spindle 6 of greater dianiet'er onwhich the roller C is mounted, said spindle 6 being provided with aremovable cone-shaped portion 6 that forms a relatively large bearingsurface for theroller Q to turn on. The spindle 5 is also provided witha removable bearing'surface 5 and the roller B is retained in positionon said spindle by'means ofaring 7 that is screwed-into the inner endof. the ,roller B. The head of the drill and the removable portion 6 ofthe spindle 6 are rovided with alining openings 8 so asto ena lo a tool,not shown, to serted in "a n "tchor'recess 9 in the f n T to holdsaid-ring while the. roller B is emg screwed ontos'ame, the roller Bacting to lock the roller 0 in operative position onits supportingspindle.

A drillof the'construction above-described can'be inserted in a. wellcasing E whose inner diameter is just great enough to receive the drill,or, in other words, is equal to the distance from the outer edge of theroller A to the outer edge of the roller 0,,

but said drill will form a hole of much reater diameter than, said casinowing to the fact that the distance from t e longitudinal center ofthehead to the outerledge of the eccentrically-disposed roller '0 isgreater than one-half the diameter of the well casing E. In other words,the diameter across the cutting surfaces of the three rollers A, B and Cis about the same as the diameter of the well casing through which thedrill is inserted,- but said rollers are so disposed with relation tothe longitudinal axis of the drill head that after the drill has beencentered with referenceto the casing it will cut a hole of greater.diameter than the casing, this, ofcourse, being due to the fact that theeccentric roller or laterally projecting roller 0 describes a circularpath of greater diameter than the casing E.

A drill of the construction above-described will under-ream a hole intowhich a surface casing E has been inserted andthus enable the casing tobe forced downwardly freely owin to the fact that the drill maintainssufficient clearance at all times to prevent the casing from binding orsticking mthe hole even though the main cutting rollers become worn tosuch an extent that they lose their clearance. The drill is as strongand rigid as an ordinary drill of this type because all of the rollersare mounted on rigid and substantial spindles on the head of the drilland when the" drill is equipped with a' narrow roller 0 or one whichadds slightly only to the cutting surface of the drill, thedrill can beused as an ordinary drill and not as an under-reamer, the extra cuttingroller (3 merely acting to maintain a liberal clearance at all times sothat there is no. possibility of the diameter of the hole becomingreduced to such an extent that 1t1s not large enough to permit thesurface case ing to be forced down through same easily.

While Iprefer to form the roller G separate and distinct from the rollerB .on ac count of the fact that it is cheaper to manufacture two rollersof the size shown thanone large roller, still-my invention ;is .3,

limited to a drill in which the eccentricallyvided with a cuttingportion B that cotiperates with the roller A to form a hole concentricwith the drill head, and a cutting portion G that erforms the samefunction as the roller O-s own in Fig. 1. It is also im material so faras m invention is concerned what particular kin ofcutting surfaces therollers are provided with, the cutting surfaces herein shown consistingof longitudi n'ally-disposed chisel-teeth 10 on each roller whichincrease gradually in' de th from the inner end of the roller outwardly,the inner end of the chisel teeth of the roller C terminating at theouter end of'the teeth of the roller B .so that a-Ishoulder will beformed at the junction of the two surfaces on which the rollers B andCoperate.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is ,1. A boring drill, comprisin a headprovided with approximately rusto-comcalshaped cutting rollers whoseaxes of rotation incline downwardly and inwardly toward the longitudinalcenter of the head and which are so arranged on the head that they willform a hole of reater diameter than the diameter across. t ecuttingfaces of said rollers.

2. .A boring drill comprising a head provided with inclinedfrusto-conical-shaped cutting rollers-which are so arranged that thearea of the cutting surface on one side of the longitudinal axis of thedrill is greater than the area of the cutting surface on the other sideof the longitudinal axis.

3. A boring drill comprising a head provided with approximately]frusto-comcalshaped cutting rollerswhose axes of rotation are inclineddownwardly and inwardly toward-the longitudinal axis ,of the head insuch a manner that they form' a hole con-' centric with. thelongitudinal axis of the drill, and means on" one side of said head forenlarging the hole formed by said rollers.

' 4. A boring drillcomprising a head, an

approximately frusto-comcal-shaped cutting device arrangl'etlon one sideof the longitudinal axis of -t ,e drill, and an approximately greaterlength and lameter arranged on the opposite sideiof the longitudinalaxis of the "drill, the axesof rotation of said devices beingfinclineddownwardly and inwardly toward the vertical centerpf'the head.

.5., .A borin drill comprising ahead provided with spindles thatmclinedownwardly and inwardly toward the longitudinal axis of the head,appreximately' ufsto-conicaL shaped cutting rollersion said spindlesthat as w form a hole concentric with the vertical axis of the drill,and an approximatel frustoconical shaped cutting device 0 greaterdiameter than-said rollers arranged in alinement with one of saidrollers at the base end of same for ,enlarging the hole formed by saidrollers,

6. A borin drill comprising a head, spindles on said head that lprojectdownwardly and inwardly toward t e lon itudinal axis of the head,approximately rusto-conicalshaped cutting rollers on said spindles whichlie on opposite sides of the longitudinal axis of the head, and anindependent approximately frusto-conical-shaped cutting roller ofgreater diameter that projects laterallyfrom one side of the head andwhose axis of rotation is in longitudinal alinement with the axis ofrotation of one of the rollers first-mentioned.

7. A roller boring drill comprising a head, an inclinedroller-supporting means on said head that projects downwardly andinwardly toward the longitudinal axis of the head, two approximatelyfrusto conical shaped cutting rollers arranged on said means one behindthe other, and an. oppositely inclined tapered cutter arrangeddiametricallyop 0- site said rollers and having a cutting sur ace ofmuch less area than the combined surfaces of said rollers.

8. A roller boring drill comprising a head, an inclined roller-supportinmeans on said head that projects downwar ly and inwardly toward thelongitudinal axis of the head, two approximately frusto-conical-shapedcutting rollers arranged on said means 'one behind the other, the outerroller operating to retain the other roller in position, means forpreventing said outer roller from becoming displaced, and a taperedcutter disposed oppositely to said outer roller and having a proximatelythe same cutting area as said outer roller.

In testimony whereof I hereunto aflix my signature in the presence oftwo witnesses, this 6th day of February, 1913.

HOWARD ROBARD HUGHES.

Witnesses:

ORE. REED, v SADE Ers'rnm.

